L3301 Leak at Lines HST Transmission Filter

[dieselscout80]

A friend has a L3301 with the hydrostatic transmission.

The two lines with three connections shown in the attached pictures are leaking where the bolts hold them to the filter base/housing and the transmission housing.

We replaced six orings and started it up and immediately it blew out two of the orings at the filter housing top port.

However, I just used orings from a generic kit I had so NOT Kubota parts.

I think the line from the transmission is the input to the filter. Is that correct?

Anyone have any insight on fixing this leak?

Could a restriction in the filter cause the leak?

On a side note it is missing the bracket that supports the filter so, I think even with Kubota parts it the leak will reoccur due to the metal lines flexing.

I think the L2501, L3301 & the 3901 are all the same just with different power output is that correct?

 

[Runs With Scissors]

That looks eerily similar to the lines I had to replace about 3 months ago when I bottomed out my tractor and bent them.

If those are the same lines, I have a wee bit of bad news for you.

Read this....

https://www.orangetractortalks.com/forums/threads/general-lees-been-hit-updated-with-new-poll.67713/


Which lead to this

https://www.orangetractortalks.com/...when-you-play-stupid-games.68050/#post-708151

I cant tell from the pics which line is leaking; If its just the small one going from the filter housing to the case of the trans, I think you dodged a bullet, but if its that bottom one, that goes forward and under the radiator, you have a little work in your future.

 

[dieselscout80]

That looks eerily similar to the lines I had to replace about 3 months ago when I bottomed out my tractor and bent them.

If those are the same lines, I have a wee bit of bad news for you.

Read this....

https://www.orangetractortalks.com/forums/threads/general-lees-been-hit-updated-with-new-poll.67713/


Which lead to this

https://www.orangetractortalks.com/...when-you-play-stupid-games.68050/#post-708151

I cant tell from the pics which line is leaking; If its just the small one going to the case, I think you dodged a bullet, but if its that bottom one, that goes forward, you have a little work in your future.

Does anyone know how much pressure those lines have if someone was going to switch to a hose?

 

[TheOldHokie]

Does anyone know how much pressure those lines have if someone was going to switch to a hose?

The only one I can actually identify is zero pressure.

 

[North Idaho Wolfman]

Without the bracket to hold the filter housing it's not going to stay sealed.

It would be a fools folly to change it to hoses.

 

[dieselscout80]

The only one I can actually identify is zero pressure.

View attachment 137423

That’s interesting because that is the one that I both heard and saw blow out after changing the orings.

I completely agree that it won’t stay sealed without the bracket supporting the filter.

 

[TheOldHokie]

That’s interesting because that is the one that I both heard and saw blow out after changing the orings.

I completely agree that it won’t stay sealed without the bracket supporting the filter.

I could be mistaken but I believe that tube is the tank return. The workshop manual is a free download....

Also quite possible that your replacement orings are the wrong size.

Dan

 

[Runs With Scissors]

The pics aren't very good, but my line were only "tweaked" a little; However, that was enough to make them leak.

You know after some reflection, I forgot to ask if it has a loader?

If it does not have a loader, then removing that line would be a little easier.

Here is a pic of the line that runs behind the loader arm bracket.

and just FYI this is the correct orientation of the O-ring set up. There are no "grooves" for the orings to fit into, which I thought was odd.

 

[TheOldHokie]

The pics aren't very good, but my line were only "tweaked" a little; However, that was enough to make them leak.

View attachment 137496 View attachment 137497

View attachment 137500





You know after some reflection, I forgot to ask if it has a loader?

If it does not have a loader, then removing that line would be a little easier.

Here is a pic of the line that runs behind the loader arm bracket.

View attachment 137498


and just FYI this is the correct orientation of the O-ring set up. There are no "grooves" for the orings to fit into, which I thought was odd.

View attachment 137501




View attachment 137502

Those are typical tube end oring seals used on low pressure connections. The jounts have to be straight and the orings need to be the correct size to get the proper amount of squeeze. Kubota seems to be using it a lot these days. Probably because it's cheap and easy to manufacture....

Dan

 

[dieselscout80]

I could be mistaken but I believe that tube is the tank return. The workshop manual is a free download....

Also quite possible that your replacement orings are the wrong size.

Dan

Dan what is the link to download the workshop manual for the L3301?

 

[TheOldHokie]

Dan what is the link to download the workshop manual for the L3301?

https://www.kubotabooks.com/AutoIndex/index.php?dir=Tractor%20Owners%20Manuals/&file=L3301%2C%20L3901%2C%20L4701%20Workshop%20manual..pdf

 

[dieselscout80]

Thanks